Study of morality (6)
I believe the answer is:
ethics
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">study of morality</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for ethics that I've seen before include "rules of conduct" , "Codes of standards in business" , "Moral principles in middle" , "Codes of conduct in business affairs" , "Study of moral values and rules" .)